The present disclosure relates to a photobioreactor for mass-culturing marine microalgae.
In recent, there is a rising interest on photosynthesis microorganisms or microalgae due to functional diversity. Also, studies with respect to the photosynthesis microorganisms or microalgae are researched in various fields. The microalgae are being actively used in studies for reducing carbon dioxide which becomes an object of attention in recent years due to environment pollution such as global warming. In addition, the microalgae are being utilized for studies related to the production of bio-energy such as biodiesel, bio-ethanol, and hydrogen gas, which are in the spotlight as the continuous energy sources in preparation for the running out of fossil fuels.
However, it should be necessary to mass-culture the microalgae at a high concentration so that carbon dioxide is significantly removed in quantity using the microalgae and useful products such as the bio-energy are mass-produced. Thus, technologies related to construction of large-scale culturing equipment are necessarily required.
In a related art, a photobioreactor having various shapes and installed in an indoor space is used as the culturing equipment for culturing the microalgae. The photobioreactor is formed of glass such expensive pyrex which increases transmittance of light and is used for pasteurization or an application material thereof. Also, the photobioreactor includes an artificial lighting unit. Thus, more capital and technologies should be invested to manufacture the photobioreactor, and much costs for maintaining/repairing and operating the photobioreactor are required after the photobioreactor is manufactured. It does cost much to expand the scale of the photobioreactor, and also, the photobioreactor involves spatial restrictions because a wide space is required for the photobioreactor. Furthermore, culture media for culturing the microalgae should be supplied and periodically replaced. Also, excreta generated when the microalgae are grown and metabolites disturbing the growth of the marine microalgae should be removed. That is, there are limitations that manufacturing costs is increased and the spatial restrictions occur. In addition, the manpower, equipment and costs for managing and operating the photobioreactor are required.
Thus, when considering that it is very important to secure economic feasibility for commercial mass-culture firstly, it does cost much to manufacture and maintain/repair the photobioreactor when a scale of the photobioreactor is expanded. In addition, the culture of the microalgae using the related-art photobioreactor in which a wide space is required and operation costs related to an operation of a lighting unit, preparation of culture media, and replacement of the culture media are involved does not a realistically appropriate way, in which the economic feasibility should be considered, for commercially mass-culturing the microalgae even though the culture of the microalgae is adequate for small scale culture which is an object of study. However, although the photobioreactor is adequate for producing expensive products such as medical supplies, reagents, high-quality chemicals, and health food supplements, the photobioreactor is not the realistically appropriate way for commercial large scale culture of the inexpensive products such as bio-energy in which the economic feasibility is very important.
As described above, the limitation related to the costs and space may act as stumbling blocks by which it is difficult to utilize the microalgae to produce useful products including the bio-energy or remove carbon dioxide. Thus, the development of the culturing technologies which cheaply and easily mass-culture the microalgae is urgently needed.